There are not really any unittest that tests this functionality so this is not caught but the following examples have changes since 1.5.0 - inset_locator_demo1 1.5.0  Master  - inset_locator_demo2 1.5.0  Master  (http://matplotlib.org/devdocs/mpl_toolkits/axes_grid/examples/inset_locator_demo2.png) - simple_axisline4 1.5.0  Master  - Simple anchored artists 1.5.0  Master  It's likely that this is only one or two issues.